<html>
<head><meta charset="utf-8"><title>steering meeting 2019.01.24 · t-compiler/wg-nll · Zulip Chat Archive</title></head>
<h2>Stream: <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/index.html">t-compiler/wg-nll</a></h2>
<h3>Topic: <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html">steering meeting 2019.01.24</a></h3>

<hr>

<base href="https://rust-lang.zulipchat.com">

<head><link href="https://rust-lang.github.io/zulip_archive/style.css" rel="stylesheet"></head>

<a name="156792301"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156792301" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156792301">(Jan 24 2019 at 18:02)</a>:</h4>
<p><span aria-label="wave" class="emoji emoji-1f44b" role="img" title="wave">:wave:</span> Hello <span class="user-group-mention" data-user-group-id="491">@WG-compiler-nll</span></p>



<a name="156792321"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156792321" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156792321">(Jan 24 2019 at 18:02)</a>:</h4>
<ul>
<li>Plan is to have a steering meeting of 1 hour to prioritize discussion of various topics:<ul>
<li>how to organize now that NLL has shipped and it’s the new year?</li>
<li>what are our big goals? (e.g., finishing the migration, polonius, plus other related features)</li>
</ul>
</li>
</ul>



<a name="156792330"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156792330" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156792330">(Jan 24 2019 at 18:02)</a>:</h4>
<p>Basically, focus is how to organize ourselves</p>



<a name="156792344"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156792344" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156792344">(Jan 24 2019 at 18:03)</a>:</h4>
<p>It'd probably be good to start off with kind of discussion of what outcomes we can expect</p>



<a name="156792406"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156792406" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> davidtwco <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156792406">(Jan 24 2019 at 18:04)</a>:</h4>
<p>(currently walking home from work so I will catch up in 15 minutes)</p>



<a name="156792486"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156792486" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156792486">(Jan 24 2019 at 18:04)</a>:</h4>
<p>one example: I think it'd be useful to come up with conditions for the various stages in finishing the migration to NLL, so that we can judge what's a blocker and what's not</p>



<a name="156792496"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156792496" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156792496">(Jan 24 2019 at 18:04)</a>:</h4>
<p>and discuss a bit how we plan to track that</p>



<a name="156792530"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156792530" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156792530">(Jan 24 2019 at 18:05)</a>:</h4>
<p>see e..g <a href="https://github.com/rust-lang/rust/issues/57804" target="_blank" title="https://github.com/rust-lang/rust/issues/57804">#57804</a></p>



<a name="156792541"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156792541" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156792541">(Jan 24 2019 at 18:05)</a>:</h4>
<p>there's turning on migrate mode for 2015</p>



<a name="156792549"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156792549" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156792549">(Jan 24 2019 at 18:05)</a>:</h4>
<p>then there's switching on full-blown NLL (not migrate mode)</p>



<a name="156792597"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156792597" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156792597">(Jan 24 2019 at 18:06)</a>:</h4>
<p>we probably should have the steps reflected in the description for <a href="https://github.com/rust-lang/rust/issues/43234" target="_blank" title="https://github.com/rust-lang/rust/issues/43234">#43234</a></p>



<a name="156792622"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156792622" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156792622">(Jan 24 2019 at 18:06)</a>:</h4>
<p>good idea</p>



<a name="156792641"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156792641" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156792641">(Jan 24 2019 at 18:06)</a>:</h4>
<p>(that description hasn't been edited since November)</p>



<a name="156792673"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156792673" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156792673">(Jan 24 2019 at 18:07)</a>:</h4>
<p>I imagine the following steps:</p>
<ul>
<li>Stage 1: NLL all the editions<br>
      - Move Rust 2015 to Migration (<a href="https://github.com/rust-lang/rust/issues/57804" target="_blank" title="https://github.com/rust-lang/rust/issues/57804">#57804</a>)<br>
      - Potential blockers:<br>
            - Known unsoundness in NLL (NLL-sound) that affects migration<br>
            - ...</li>
<li>Stage 2: Transition fully to NLL <br>
      - Potential blockers:<br>
            - Known unsoundness in NLL (NLL-sound) that affects NLL mode without migration<br>
            - ...</li>
<li>Stage 3: Remove old checker</li>
</ul>



<a name="156792676"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156792676" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156792676">(Jan 24 2019 at 18:07)</a>:</h4>
<p>I can take the action item of trying to update it, most likely based on the discussion we are having right now. :)</p>



<a name="156792752"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156792752" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156792752">(Jan 24 2019 at 18:08)</a>:</h4>
<p>hmm Zulip doesn't seem to like my nested list ;)</p>



<a name="156792775"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156792775" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156792775">(Jan 24 2019 at 18:08)</a>:</h4>
<p>Moving from borrowck=migrate to borrowck=mir may require revisiting the analysis of diagnostic parity</p>



<a name="156792777"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156792777" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Matthew Jasper <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156792777">(Jan 24 2019 at 18:08)</a>:</h4>
<ul>
<li>diagnostics are reasonable and no known serrors regressions</li>
</ul>



<a name="156792788"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156792788" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156792788">(Jan 24 2019 at 18:08)</a>:</h4>
<p>yes I was going to bring up diagnostics</p>



<a name="156792789"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156792789" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Matthew Jasper <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156792789">(Jan 24 2019 at 18:08)</a>:</h4>
<p>Serious</p>



<a name="156792790"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156792790" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156792790">(Jan 24 2019 at 18:08)</a>:</h4>
<p>heh great minds think alike ... and so do we</p>



<a name="156792793"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156792793" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156792793">(Jan 24 2019 at 18:08)</a>:</h4>
<p>one interesting question is something like the NLL 2PB thing</p>



<a name="156792795"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156792795" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156792795">(Jan 24 2019 at 18:08)</a>:</h4>
<p>i.e., if there are <em>unresolved questions</em></p>



<a name="156792798"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156792798" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156792798">(Jan 24 2019 at 18:08)</a>:</h4>
<p>do we want to "limit the spread of NLL"</p>



<a name="156792802"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156792802" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156792802">(Jan 24 2019 at 18:08)</a>:</h4>
<p>until they are resolved</p>



<a name="156792807"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156792807" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156792807">(Jan 24 2019 at 18:08)</a>:</h4>
<p>or does it not matter anyway</p>



<a name="156792834"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156792834" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156792834">(Jan 24 2019 at 18:09)</a>:</h4>
<p>do we have enough feedback in general, or is no feedback == good news ? whether about the behaviour or diagnostics</p>



<a name="156792836"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156792836" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156792836">(Jan 24 2019 at 18:09)</a>:</h4>
<p>(I think that is the only such question?)</p>



<a name="156792847"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156792847" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156792847">(Jan 24 2019 at 18:09)</a>:</h4>
<p>(the "limit the spread of NLL" ship may have sailed...)</p>



<a name="156792850"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156792850" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156792850">(Jan 24 2019 at 18:09)</a>:</h4>
<p>I feel ok about feedback. I've mostly just heard positive things</p>



<a name="156792855"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156792855" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156792855">(Jan 24 2019 at 18:09)</a>:</h4>
<blockquote>
<p>(the "limit the spread of NLL" ship may have sailed...)</p>
</blockquote>
<p>this is my sense too</p>



<a name="156792860"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156792860" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156792860">(Jan 24 2019 at 18:09)</a>:</h4>
<p>at first I wanted to wait to extend to 2015</p>



<a name="156792864"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156792864" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156792864">(Jan 24 2019 at 18:09)</a>:</h4>
<p>but now I'm guessing..that may not matter so much</p>



<a name="156792926"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156792926" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156792926">(Jan 24 2019 at 18:10)</a>:</h4>
<p>of course, I don't really have any data for why that is</p>



<a name="156792972"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156792972" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Matthew Jasper <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156792972">(Jan 24 2019 at 18:10)</a>:</h4>
<p>For 2PB I think we can start with the most conservative version, and move to a final decision on a separate schedule.</p>



<a name="156792995"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156792995" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156792995">(Jan 24 2019 at 18:10)</a>:</h4>
<p>well, the main point is: do we want to block enabling 2015 on having that conservative version in place?</p>



<a name="156793020"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793020" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793020">(Jan 24 2019 at 18:11)</a>:</h4>
<p>I think I would definitely block the move away from migration</p>



<a name="156793030"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793030" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793030">(Jan 24 2019 at 18:11)</a>:</h4>
<p>ah, <em>that</em> reminds me</p>



<a name="156793042"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793042" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793042">(Jan 24 2019 at 18:11)</a>:</h4>
<p>for the move from migration to "full version", that also currently means that you get hard errors (right?)</p>



<a name="156793056"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793056" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793056">(Jan 24 2019 at 18:11)</a>:</h4>
<p>so perhaps we want some measurements here</p>



<a name="156793068"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793068" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793068">(Jan 24 2019 at 18:11)</a>:</h4>
<p>e.g., we probably want to apply the "no major crater regressions" rule</p>



<a name="156793069"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793069" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793069">(Jan 24 2019 at 18:11)</a>:</h4>
<p>what kind of measurements?</p>



<a name="156793078"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793078" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793078">(Jan 24 2019 at 18:11)</a>:</h4>
<p>oh I see</p>



<a name="156793085"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793085" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Matthew Jasper <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793085">(Jan 24 2019 at 18:12)</a>:</h4>
<p>I would say yes, but I don't think it will take that long to have the conservative version working. (We should block migrate on 2015 on 2PB)</p>



<a name="156793127"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793127" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793127">(Jan 24 2019 at 18:12)</a>:</h4>
<p>same as any breaking change bug fix</p>



<a name="156793209"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793209" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793209">(Jan 24 2019 at 18:13)</a>:</h4>
<p>does that somehow require coordinating with ralf and their stacked borrows model (sorry I'm not up to date on these latest discussions) ?</p>



<a name="156793315"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793315" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793315">(Jan 24 2019 at 18:14)</a>:</h4>
<p>well ... I don't know if turning it on requires <em>coordination</em> per se</p>



<a name="156793339"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793339" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793339">(Jan 24 2019 at 18:15)</a>:</h4>
<p>under the assumption that if we implement it, ralf will be happy ...</p>



<a name="156793341"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793341" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793341">(Jan 24 2019 at 18:15)</a>:</h4>
<p>I moved my outline to the dropbox paper document, <a href="https://paper.dropbox.com/doc/Non-lexical-lifetimes-NLL-Triage--AWTKee_yJi_~4jlT~qHeiofBAg-Em2cJrvxQMMFWLE7lE5Be#:h2=Transition-to-NLL:" target="_blank" title="https://paper.dropbox.com/doc/Non-lexical-lifetimes-NLL-Triage--AWTKee_yJi_~4jlT~qHeiofBAg-Em2cJrvxQMMFWLE7lE5Be#:h2=Transition-to-NLL:">link</a></p>



<a name="156793347"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793347" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793347">(Jan 24 2019 at 18:15)</a>:</h4>
<p>but that may be naive of me</p>



<a name="156793350"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793350" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793350">(Jan 24 2019 at 18:15)</a>:</h4>
<blockquote>
<p>does that somehow require coordinating with ralf and their stacked borrows model (sorry I'm not up to date on these latest discussions) ?</p>
</blockquote>
<p>no, because we are aiming to do a conservative thing</p>



<a name="156793356"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793356" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793356">(Jan 24 2019 at 18:15)</a>:</h4>
<p>that is, moving to the <em>conservative</em> thing does not in particular</p>



<a name="156793366"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793366" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793366">(Jan 24 2019 at 18:15)</a>:</h4>
<p>moving back to the current version (or something like it) would</p>



<a name="156793424"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793424" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793424">(Jan 24 2019 at 18:16)</a>:</h4>
<p>or at least it is a decision that should be made with an eye towards the effects on stacked borrows</p>



<a name="156793443"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793443" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793443">(Jan 24 2019 at 18:16)</a>:</h4>
<blockquote>
<p>I moved my outline to the dropbox paper document, <a href="https://paper.dropbox.com/doc/Non-lexical-lifetimes-NLL-Triage--AWTKee_yJi_~4jlT~qHeiofBAg-Em2cJrvxQMMFWLE7lE5Be#:h2=Transition-to-NLL:" target="_blank" title="https://paper.dropbox.com/doc/Non-lexical-lifetimes-NLL-Triage--AWTKee_yJi_~4jlT~qHeiofBAg-Em2cJrvxQMMFWLE7lE5Be#:h2=Transition-to-NLL:">link</a></p>
</blockquote>
<p>(feel free to edit or add comments)</p>



<a name="156793444"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793444" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793444">(Jan 24 2019 at 18:16)</a>:</h4>
<p>alright ok, then yeah probably best to have them in order to switch 2015 to migrate then ?</p>



<a name="156793454"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793454" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793454">(Jan 24 2019 at 18:16)</a>:</h4>
<p>"to have them"?</p>



<a name="156793458"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793458" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793458">(Jan 24 2019 at 18:16)</a>:</h4>
<p>get the conservative version working</p>



<a name="156793467"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793467" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793467">(Jan 24 2019 at 18:17)</a>:</h4>
<p>well that was what we were discussing</p>



<a name="156793469"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793469" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793469">(Jan 24 2019 at 18:17)</a>:</h4>
<p>I'm not sure how much it matters</p>



<a name="156793476"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793476" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793476">(Jan 24 2019 at 18:17)</a>:</h4>
<p>it'd be nice though</p>



<a name="156793478"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793478" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793478">(Jan 24 2019 at 18:17)</a>:</h4>
<p>definitely before we move away from migration mode</p>



<a name="156793480"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793480" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793480">(Jan 24 2019 at 18:17)</a>:</h4>
<blockquote>
<p>get the conservative version working</p>
</blockquote>
<p>yeah, i think that's why niko said he'd block going from migration to borrowck=mir on it</p>



<a name="156793497"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793497" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793497">(Jan 24 2019 at 18:17)</a>:</h4>
<p>in particular, until we move to borrowck=mir:</p>
<ul>
<li>you'll be getting warnings, not hard errors, from the cases that we change</li>
</ul>



<a name="156793501"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793501" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793501">(Jan 24 2019 at 18:17)</a>:</h4>
<p>we don't really have any sort of deadline for this, that I know of</p>



<a name="156793511"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793511" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793511">(Jan 24 2019 at 18:17)</a>:</h4>
<p>that is, when we make the rule more conservative, it won't immediately cause errors</p>



<a name="156793518"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793518" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793518">(Jan 24 2019 at 18:17)</a>:</h4>
<p>so we can kind of roll those fixes into the general borrowck=mir move criteria</p>



<a name="156793568"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793568" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793568">(Jan 24 2019 at 18:18)</a>:</h4>
<p>its mostly just "its good to get it out of the way" (so that 1. everyone can benefit from NLL on the 2015 edition, and 2. so that we can focus effort on other tasks, like Polonius</p>



<a name="156793582"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793582" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793582">(Jan 24 2019 at 18:18)</a>:</h4>
<blockquote>
<p>we don't really have any sort of deadline for this, that I know of</p>
</blockquote>
<p>no -- it might be nice to hvae a kind of target? not sure how important it is. I mostly wanted to discuss the criteria and how we will track blocking issues (should we make a meta-issue?)</p>



<a name="156793611"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793611" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793611">(Jan 24 2019 at 18:19)</a>:</h4>
<p>anyway, I feel kind of good about the outline, and I guess a meta-issue like <a href="https://github.com/rust-lang/rust/issues/57804" target="_blank" title="https://github.com/rust-lang/rust/issues/57804">#57804</a> is ok?</p>



<a name="156793617"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793617" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793617">(Jan 24 2019 at 18:19)</a>:</h4>
<blockquote>
<p>(should we make a meta-issue?)</p>
</blockquote>
<p>shouldn't the existing tracking issue suffice?</p>



<a name="156793631"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793631" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793631">(Jan 24 2019 at 18:19)</a>:</h4>
<p>I would prefer an issue specific to this transition</p>



<a name="156793644"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793644" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793644">(Jan 24 2019 at 18:19)</a>:</h4>
<p>ok, so that's an action item, to make such an issue</p>



<a name="156793648"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793648" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793648">(Jan 24 2019 at 18:19)</a>:</h4>
<p>seems easy enough :)</p>



<a name="156793653"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793653" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793653">(Jan 24 2019 at 18:19)</a>:</h4>
<p>(the alternative might be GH projects or something)</p>



<a name="156793752"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793752" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Matthew Jasper <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793752">(Jan 24 2019 at 18:20)</a>:</h4>
<p>Shall we leave discussion of stage 3 until after we have stage 1 and 2 mostly done?</p>



<a name="156793765"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793765" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793765">(Jan 24 2019 at 18:20)</a>:</h4>
<p>related question:</p>
<p>Do we want to block moving to borrowck=mir on having migated all existing uses of the old lexical checker? I don't see why we should, I guess (example would be things like wf checking and so forth)</p>



<a name="156793780"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793780" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793780">(Jan 24 2019 at 18:21)</a>:</h4>
<p>yeah, I don't think we have to go into stage 3 just yet</p>



<a name="156793783"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793783" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Matthew Jasper <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793783">(Jan 24 2019 at 18:21)</a>:</h4>
<p>I'm hoping for 1.34 - migrate on 2015, 1.35 - full NLL on 2018 1.37 - full NLL everywhere.</p>



<a name="156793791"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793791" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793791">(Jan 24 2019 at 18:21)</a>:</h4>
<p>oh, I hadn't considered the idea of turning on full NLL only for 2018</p>



<a name="156793800"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793800" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793800">(Jan 24 2019 at 18:21)</a>:</h4>
<p>I was assuming that we'd just throw the switch for all editions</p>



<a name="156793869"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793869" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793869">(Jan 24 2019 at 18:22)</a>:</h4>
<p>would turning on full NLL in 2018 and then 2015 be a "just in case" insurance (in case 2018 is the smaller rollout of the 2) ?</p>



<a name="156793915"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793915" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793915">(Jan 24 2019 at 18:23)</a>:</h4>
<p>i think we're probably better off throwing the switch for everyone.</p>



<a name="156793930"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793930" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793930">(Jan 24 2019 at 18:23)</a>:</h4>
<p>it will let us find out about problems sooner, and simplify bug reporting/reproduction</p>



<a name="156793954"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156793954" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156793954">(Jan 24 2019 at 18:23)</a>:</h4>
<p>The transition from migrate to full NLL has relatively small effect, compared to the original introduction of NLL</p>



<a name="156794000"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794000" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Matthew Jasper <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794000">(Jan 24 2019 at 18:24)</a>:</h4>
<p>I think that we need migrate mode on 2015 for a few releases before enabling full NLL, and that that would be what limits us stabilizing.</p>



<a name="156794004"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794004" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794004">(Jan 24 2019 at 18:24)</a>:</h4>
<p>so I don't see as much incentive for a migration path</p>



<a name="156794021"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794021" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794021">(Jan 24 2019 at 18:24)</a>:</h4>
<p>hmm</p>



<a name="156794035"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794035" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794035">(Jan 24 2019 at 18:24)</a>:</h4>
<blockquote>
<p>I think that we need migrate mode on 2015 for a few releases before enabling full NLL, and that that would be what limits us stabilizing.</p>
</blockquote>
<p>okay this is worth thinking about</p>



<a name="156794040"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794040" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794040">(Jan 24 2019 at 18:24)</a>:</h4>
<blockquote>
<p>I think that we need migrate mode on 2015 for a few releases before enabling full NLL, and that that would be what limits us stabilizing.</p>
</blockquote>
<p>basically because 2015 folks are not yet getting warnings?</p>



<a name="156794045"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794045" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Matthew Jasper <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794045">(Jan 24 2019 at 18:24)</a>:</h4>
<p>Yes</p>



<a name="156794050"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794050" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Santiago Pastorino <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794050">(Jan 24 2019 at 18:24)</a>:</h4>
<p>yes that seems wise :)</p>



<a name="156794054"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794054" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794054">(Jan 24 2019 at 18:24)</a>:</h4>
<p>well, let's add this as an unresolved question</p>



<a name="156794059"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794059" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794059">(Jan 24 2019 at 18:25)</a>:</h4>
<p>I'm sort of inclined to not distinguish editions</p>



<a name="156794062"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794062" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794062">(Jan 24 2019 at 18:25)</a>:</h4>
<p>and just wait for everyone</p>



<a name="156794073"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794073" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794073">(Jan 24 2019 at 18:25)</a>:</h4>
<p>but .. maybe it's wise to start giving hard errors</p>



<a name="156794079"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794079" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794079">(Jan 24 2019 at 18:25)</a>:</h4>
<p>it hasn't proven to be a big source of confusion thus far</p>



<a name="156794090"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794090" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794090">(Jan 24 2019 at 18:25)</a>:</h4>
<p>I'm mostly just wary of having "ifs" in the compiler in general</p>



<a name="156794094"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794094" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Matthew Jasper <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794094">(Jan 24 2019 at 18:25)</a>:</h4>
<p>If it takes a few months to be ready, then I'm fine stabilizing both together</p>



<a name="156794108"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794108" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794108">(Jan 24 2019 at 18:25)</a>:</h4>
<p>a few months after what point?</p>



<a name="156794112"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794112" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794112">(Jan 24 2019 at 18:25)</a>:</h4>
<p>there is another intermediate step</p>



<a name="156794114"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794114" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794114">(Jan 24 2019 at 18:25)</a>:</h4>
<p>that we can do</p>



<a name="156794120"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794120" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794120">(Jan 24 2019 at 18:25)</a>:</h4>
<p>which is, we can shift the warnings from warnings to deny-by-default lints</p>



<a name="156794122"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794122" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794122">(Jan 24 2019 at 18:25)</a>:</h4>
<p>a few months after we enable borrowck=migrate  for 2015 edition?</p>



<a name="156794126"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794126" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Matthew Jasper <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794126">(Jan 24 2019 at 18:26)</a>:</h4>
<p>Yes</p>



<a name="156794127"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794127" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794127">(Jan 24 2019 at 18:26)</a>:</h4>
<p>this is often a good idea if we want to encourage people to migate :)</p>



<a name="156794230"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794230" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794230">(Jan 24 2019 at 18:27)</a>:</h4>
<p>for some reason I have this vague impression that we would have problems turning this into a proper lint</p>



<a name="156794241"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794241" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794241">(Jan 24 2019 at 18:27)</a>:</h4>
<p>am I misremembering the current state of the lint infrastructure w.r.t. MIR analyses?</p>



<a name="156794242"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794242" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794242">(Jan 24 2019 at 18:27)</a>:</h4>
<p>hmm, ok, so this is an interesting question. Basically the options for roll out are:</p>
<ul>
<li>Enable Migrate-NLL on 2015</li>
<li>Convert Migrate-NLL on 2018 to deny-by-default</li>
<li>Convert Migrate-NLL on 2015 to deny-by-default</li>
<li>Convert 2018 to hard error</li>
<li>Convert 2015 to hard error</li>
</ul>
<p>where some of those steps can be combined</p>



<a name="156794248"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794248" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794248">(Jan 24 2019 at 18:27)</a>:</h4>
<p>i.e., we might make it deny-by-default on all editions first</p>



<a name="156794251"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794251" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794251">(Jan 24 2019 at 18:27)</a>:</h4>
<p>I guess a crater run around the time to turn borrowck=migrate on 2015 would be an interesting datapoint wrt warnings and deny-by-default lints</p>



<a name="156794305"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794305" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794305">(Jan 24 2019 at 18:28)</a>:</h4>
<blockquote>
<p>for some reason I have this vague impression that we would have problems turning this into a proper lint</p>
</blockquote>
<p>oh, it's not a proper lint? why should that be hard? I mean, you could just use the node-id of the fn</p>



<a name="156794319"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794319" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> blitzerr <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794319">(Jan 24 2019 at 18:28)</a>:</h4>
<blockquote>
<p>hmm, ok, so this is an interesting question. Basically the options for roll out are:</p>
<ul>
<li>Enable Migrate-NLL on 2015</li>
<li>Convert Migrate-NLL on 2018 to deny-by-default</li>
<li>Convert Migrate-NLL on 2015 to deny-by-default</li>
<li>Convert 2018 to hard error</li>
<li>Convert 2015 to hard error</li>
</ul>
<p>where some of those steps can be combined</p>
</blockquote>
<p>How long do we expect it to take for all of them ?</p>



<a name="156794326"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794326" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794326">(Jan 24 2019 at 18:28)</a>:</h4>
<p>(the main reason to use a lint is cap-dependencies)</p>



<a name="156794355"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794355" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794355">(Jan 24 2019 at 18:28)</a>:</h4>
<blockquote>
<p>oh, it's not a proper lint? why should that be hard? I mean, you could just use the node-id of the fn</p>
</blockquote>
<p>I'll just go double-check</p>



<a name="156794384"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794384" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794384">(Jan 24 2019 at 18:29)</a>:</h4>
<p>well anyway it's not too important</p>



<a name="156794395"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794395" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794395">(Jan 24 2019 at 18:29)</a>:</h4>
<p>I think we don't have to decide now whether to (e.g.) do deny-by-default first</p>



<a name="156794406"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794406" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794406">(Jan 24 2019 at 18:30)</a>:</h4>
<p>it seems like we can collect issues that would block going to NLL 100% in a tracking issue</p>



<a name="156794453"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794453" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794453">(Jan 24 2019 at 18:30)</a>:</h4>
<p>and if we decide we want to make a smaller step (e.g., going to NLL in 2018 only)</p>



<a name="156794467"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794467" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794467">(Jan 24 2019 at 18:30)</a>:</h4>
<p>we can do that and make a new stage "on the fly"</p>



<a name="156794478"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794478" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794478">(Jan 24 2019 at 18:30)</a>:</h4>
<p>anyway, I imagine that going to hard errors and not warnings on 2018 only has basically the same pre-reqs</p>



<a name="156794483"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794483" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794483">(Jan 24 2019 at 18:30)</a>:</h4>
<p><strong>except</strong> that it affects the crater run results</p>



<a name="156794487"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794487" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794487">(Jan 24 2019 at 18:30)</a>:</h4>
<p>(does that sound right?)</p>



<a name="156794507"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794507" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794507">(Jan 24 2019 at 18:31)</a>:</h4>
<blockquote>
<blockquote>
<p>hmm, ok, so this is an interesting question. Basically the options for roll out are: [...]</p>
<p>where some of those steps can be combined</p>
</blockquote>
<p>How long do we expect it to take for all of them ?</p>
</blockquote>
<p>I think the main time-delays would be in us releasing the result and waiting for feedback</p>



<a name="156794615"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794615" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794615">(Jan 24 2019 at 18:32)</a>:</h4>
<blockquote>
<p><strong>except</strong> that it affects the crater run results</p>
</blockquote>
<p>in the sense that the majority of <a href="http://crates.io" target="_blank" title="http://crates.io">crates.io</a> right now is going to be 2015 edition code</p>



<a name="156794618"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794618" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794618">(Jan 24 2019 at 18:32)</a>:</h4>
<p>right?</p>



<a name="156794622"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794622" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794622">(Jan 24 2019 at 18:32)</a>:</h4>
<p>yes</p>



<a name="156794637"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794637" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794637">(Jan 24 2019 at 18:32)</a>:</h4>
<p>i.e., we still want all the soundness bugs fixed</p>



<a name="156794654"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794654" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794654">(Jan 24 2019 at 18:32)</a>:</h4>
<p>but we might be able to move faster on 2018 only because it affects less code, and that code is more likely to have been updated</p>



<a name="156794664"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794664" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794664">(Jan 24 2019 at 18:33)</a>:</h4>
<p>seems like we would definitely want to do it across all editions for the <strong>initial</strong> crater runs</p>



<a name="156794675"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794675" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794675">(Jan 24 2019 at 18:33)</a>:</h4>
<p>just to cast as wide a net as possible</p>



<a name="156794682"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794682" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794682">(Jan 24 2019 at 18:33)</a>:</h4>
<p>we don't have to commit to that approach in what we deploy</p>



<a name="156794688"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794688" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794688">(Jan 24 2019 at 18:33)</a>:</h4>
<p>so basically</p>



<a name="156794689"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794689" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794689">(Jan 24 2019 at 18:33)</a>:</h4>
<p>So I think the effect on crater is actually ... independent?</p>



<a name="156794690"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794690" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794690">(Jan 24 2019 at 18:33)</a>:</h4>
<p>it doesn't matter <strong>yet</strong></p>



<a name="156794696"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794696" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794696">(Jan 24 2019 at 18:33)</a>:</h4>
<p>this is something we can decide once we have the crater results in place</p>



<a name="156794698"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794698" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794698">(Jan 24 2019 at 18:33)</a>:</h4>
<p>i.e., first we have to fix all the bugs</p>



<a name="156794702"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794702" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794702">(Jan 24 2019 at 18:33)</a>:</h4>
<p>and get the other steps done</p>



<a name="156794747"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794747" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> davidtwco <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794747">(Jan 24 2019 at 18:34)</a>:</h4>
<p><span aria-label="thumbs up" class="emoji emoji-1f44d" role="img" title="thumbs up">:thumbs_up:</span> for everything so far</p>



<a name="156794751"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794751" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794751">(Jan 24 2019 at 18:34)</a>:</h4>
<p>the lint idea sounds like an interesting possible step in any case</p>



<a name="156794758"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794758" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794758">(Jan 24 2019 at 18:34)</a>:</h4>
<p>if that is done and we have bad crater results, or 2015 hasn't had "enough time" to bake, then we decide to try 2018 only</p>



<a name="156794842"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794842" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794842">(Jan 24 2019 at 18:34)</a>:</h4>
<p>this all sounds both correct and good to me</p>



<a name="156794884"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794884" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794884">(Jan 24 2019 at 18:35)</a>:</h4>
<p>so that's one goal: Finish migration</p>



<a name="156794893"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794893" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794893">(Jan 24 2019 at 18:35)</a>:</h4>
<p>I can't imagine that taking up the whole year</p>



<a name="156794904"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794904" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794904">(Jan 24 2019 at 18:35)</a>:</h4>
<p><strong>unless</strong> we decide to make it so</p>



<a name="156794966"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794966" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794966">(Jan 24 2019 at 18:36)</a>:</h4>
<p>in the sense that we decide to adopt a plan that has so many steps</p>



<a name="156794973"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794973" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794973">(Jan 24 2019 at 18:36)</a>:</h4>
<p>that we are waiting for user feedback a lot</p>



<a name="156794976"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794976" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794976">(Jan 24 2019 at 18:36)</a>:</h4>
<p>which would be fine</p>



<a name="156794982"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794982" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794982">(Jan 24 2019 at 18:36)</a>:</h4>
<p>But since that is time spent waiting</p>



<a name="156794987"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156794987" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156794987">(Jan 24 2019 at 18:36)</a>:</h4>
<p>it is time that we can use for other things</p>



<a name="156795023"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795023" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795023">(Jan 24 2019 at 18:37)</a>:</h4>
<p>so: any interest in talking about polonius goals for this year?</p>



<a name="156795098"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795098" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795098">(Jan 24 2019 at 18:38)</a>:</h4>
<p>would we want a Minimum Viable Polonius for example ?</p>



<a name="156795099"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795099" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795099">(Jan 24 2019 at 18:38)</a>:</h4>
<p>Apart from migration, I see a few things on my list:</p>
<ul>
<li>Polonius<br>
    - beyond the obvious, there are some other interesting question marks here, e.g. should we increase scope to things like move and initialization analysis?</li>
<li>The closure work that <span class="user-mention" data-user-id="128294">@blitzerr</span> has been doing (<a href="https://github.com/rust-lang/rfcs/pull/2229" target="_blank" title="https://github.com/rust-lang/rfcs/pull/2229">RFC #2229</a>), which is not <em>directly</em> related to NLL</li>
<li>Converting all uses of lexical solver, even those outside of a "control-flow context"<br>
    - I feel like this intersects the region solve a bit too and polonius perhaps</li>
<li>General code cleanup<br>
    - My sense is that the borrow checker etc could somehow use to be "tidied up", but I don't have specific suggestions right now. If nothing else, the files are too big. :P</li>
</ul>



<a name="156795155"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795155" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795155">(Jan 24 2019 at 18:39)</a>:</h4>
<p>I guess it seems, from that list, a strategy around Polonius might be the most fruitful thing to discuss at this moment</p>



<a name="156795167"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795167" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795167">(Jan 24 2019 at 18:39)</a>:</h4>
<p>(as others suggested before I sent my Wall-o-text)</p>



<a name="156795221"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795221" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795221">(Jan 24 2019 at 18:40)</a>:</h4>
<p>do we <em>have</em> to e.g implement move and initialization analysis in Polonius, to see how it impacts rustc, compile times and so on (which we have at the moment, not a very good idea of) ?</p>



<a name="156795243"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795243" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795243">(Jan 24 2019 at 18:40)</a>:</h4>
<p>well</p>



<a name="156795244"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795244" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795244">(Jan 24 2019 at 18:40)</a>:</h4>
<p>no</p>



<a name="156795248"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795248" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795248">(Jan 24 2019 at 18:40)</a>:</h4>
<p>I mean we can go on using the code we are using now</p>



<a name="156795252"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795252" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795252">(Jan 24 2019 at 18:40)</a>:</h4>
<p>I do think we want to replace the existing region solver code</p>



<a name="156795256"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795256" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795256">(Jan 24 2019 at 18:40)</a>:</h4>
<p>because right now we're doing purely extra work, effectively</p>



<a name="156795262"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795262" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795262">(Jan 24 2019 at 18:41)</a>:</h4>
<p>for that reason alone, it's probably a good idea to put off the move/initialization stuff</p>



<a name="156795272"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795272" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795272">(Jan 24 2019 at 18:41)</a>:</h4>
<p>just so we can independently measure its effects</p>



<a name="156795280"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795280" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Santiago Pastorino <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795280">(Jan 24 2019 at 18:41)</a>:</h4>
<p>seems good</p>



<a name="156795282"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795282" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795282">(Jan 24 2019 at 18:41)</a>:</h4>
<p>what would be the expected benefits of doing move/init analyses in Polonius?</p>



<a name="156795290"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795290" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795290">(Jan 24 2019 at 18:41)</a>:</h4>
<p>would the downstream analyses in Polonius gain some sort of efficiency?</p>



<a name="156795293"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795293" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795293">(Jan 24 2019 at 18:41)</a>:</h4>
<p>I assume the actual results would not change</p>



<a name="156795296"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795296" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795296">(Jan 24 2019 at 18:41)</a>:</h4>
<p>personally, I want to move towards doing as much as possible using datafrog-style rules</p>



<a name="156795299"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795299" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795299">(Jan 24 2019 at 18:41)</a>:</h4>
<p>for uniformity</p>



<a name="156795312"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795312" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795312">(Jan 24 2019 at 18:41)</a>:</h4>
<p>and because it makes things better specified</p>



<a name="156795313"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795313" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795313">(Jan 24 2019 at 18:42)</a>:</h4>
<p>so more like a cleanup kind of task</p>



<a name="156795359"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795359" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795359">(Jan 24 2019 at 18:42)</a>:</h4>
<p>however, I don't know what perf impact will be really.</p>



<a name="156795362"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795362" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795362">(Jan 24 2019 at 18:42)</a>:</h4>
<p>yes okay there' also the benefit that it cleans up the code</p>



<a name="156795366"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795366" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795366">(Jan 24 2019 at 18:42)</a>:</h4>
<p>I would not be surprised if it were better</p>



<a name="156795369"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795369" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795369">(Jan 24 2019 at 18:42)</a>:</h4>
<p>(but I also would not be surprised if there are cases where it is worse)</p>



<a name="156795377"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795377" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795377">(Jan 24 2019 at 18:42)</a>:</h4>
<p>but yeah I don't think we gain expressiveness from it</p>



<a name="156795396"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795396" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795396">(Jan 24 2019 at 18:42)</a>:</h4>
<p>(unless we did something funky)</p>



<a name="156795416"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795416" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795416">(Jan 24 2019 at 18:43)</a>:</h4>
<p>I guess in general I'd like to push as much of the logic into datafrog as we can, so that the inputs we are producing are simple and something we can "directly" read out from the MIR</p>



<a name="156795423"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795423" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Santiago Pastorino <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795423">(Jan 24 2019 at 18:43)</a>:</h4>
<p>the idea of making polonius run the naive analysis unless it fails still holds?</p>



<a name="156795429"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795429" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Santiago Pastorino <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795429">(Jan 24 2019 at 18:43)</a>:</h4>
<p>and how do you imagine the performance in those cases?</p>



<a name="156795442"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795442" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795442">(Jan 24 2019 at 18:43)</a>:</h4>
<blockquote>
<p>unless we did something funky</p>
</blockquote>
<p>well what I guess I mean is: I think we could implement e.g. the rules around initializing fields out of order, but I think we could do that with today's system too</p>



<a name="156795458"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795458" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795458">(Jan 24 2019 at 18:43)</a>:</h4>
<p><span class="user-mention" data-user-id="116266">@Santiago Pastorino</span>  you mean the location insensitive analysis, not the naive one right ?</p>



<a name="156795508"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795508" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Santiago Pastorino <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795508">(Jan 24 2019 at 18:44)</a>:</h4>
<p>ahh ya, sorry, location insensitive yes</p>



<a name="156795512"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795512" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795512">(Jan 24 2019 at 18:44)</a>:</h4>
<blockquote>
<p>and how do you imagine the performance in those cases?</p>
</blockquote>
<p>ah so yes this is part of my calculus: I think that once we move to rules that we express in datalog, we can also more readily do optimized variants</p>



<a name="156795516"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795516" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Santiago Pastorino <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795516">(Jan 24 2019 at 18:44)</a>:</h4>
<p>wasn't remembering the names properly :)</p>



<a name="156795520"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795520" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795520">(Jan 24 2019 at 18:44)</a>:</h4>
<p>e.g., maybe there is a location insensitive version of the move-initialization rules we can do</p>



<a name="156795558"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795558" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Santiago Pastorino <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795558">(Jan 24 2019 at 18:45)</a>:</h4>
<p>shouldn't a strategy like that when you compare a huge program, cause a lot of benefits?</p>



<a name="156795584"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795584" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Santiago Pastorino <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795584">(Jan 24 2019 at 18:45)</a>:</h4>
<p>I'd expect you need location sensitive the less than location insensitive</p>



<a name="156795587"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795587" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795587">(Jan 24 2019 at 18:45)</a>:</h4>
<p>potentially, I guess it depends what %age of compilation time is spent in those checks :)</p>



<a name="156795591"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795591" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Santiago Pastorino <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795591">(Jan 24 2019 at 18:45)</a>:</h4>
<p>yep</p>



<a name="156795592"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795592" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795592">(Jan 24 2019 at 18:45)</a>:</h4>
<p>but that is the hope, certainly</p>



<a name="156795600"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795600" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Santiago Pastorino <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795600">(Jan 24 2019 at 18:45)</a>:</h4>
<p>yes</p>



<a name="156795603"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795603" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795603">(Jan 24 2019 at 18:45)</a>:</h4>
<p>is it still possible that the polonius code is not the way we decide to go for "NLL 2.0" (what we punted from MIR borrowck into polonius) ? (e.g if it somehow performs extremely worse on benchmarks)</p>



<a name="156795605"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795605" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Santiago Pastorino <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795605">(Jan 24 2019 at 18:45)</a>:</h4>
<p>don't guess, measure</p>



<a name="156795607"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795607" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Santiago Pastorino <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795607">(Jan 24 2019 at 18:46)</a>:</h4>
<p>just thinking on possibilities</p>



<a name="156795664"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795664" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795664">(Jan 24 2019 at 18:46)</a>:</h4>
<blockquote>
<p>is it still possible that the polonius code is not the way we decide to go for "NLL 2.0" (what we punted from MIR borrowck into polonius) ? (e.g if it somehow performs extremely worse on benchmarks)</p>
</blockquote>
<p>I suppose so</p>



<a name="156795682"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795682" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795682">(Jan 24 2019 at 18:46)</a>:</h4>
<p>(I'd still declare victory even if that happened)</p>



<a name="156795688"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795688" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795688">(Jan 24 2019 at 18:46)</a>:</h4>
<p>so, I guess the meta question is: how do we want to manage the polonius stuff? I mean, maybe one question worth asking: should we make a WG-polonius?</p>



<a name="156795712"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795712" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795712">(Jan 24 2019 at 18:47)</a>:</h4>
<p>(with e.g. a separate triage meeting and cycle?)</p>



<a name="156795732"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795732" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795732">(Jan 24 2019 at 18:47)</a>:</h4>
<p>considering how out of the loop I have been regarding Polonius, I would not object to a WG-polonius</p>



<a name="156795733"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795733" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795733">(Jan 24 2019 at 18:47)</a>:</h4>
<p>would the WG be made in order to allow current wg-nll members to focus on non-polonius things ?</p>



<a name="156795795"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795795" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795795">(Jan 24 2019 at 18:48)</a>:</h4>
<p>I guess my reasoning was a few things. I tend to view working groups as being focused on a goal, not perpetual entities. And it feels like the goal for wg-nll is in sight, and we should focus on it</p>



<a name="156795802"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795802" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795802">(Jan 24 2019 at 18:48)</a>:</h4>
<p>but also that the tasks for polonius are quite distinct from the "migration" tasks</p>



<a name="156795805"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795805" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795805">(Jan 24 2019 at 18:48)</a>:</h4>
<p>so maybe it's not helpful to conflate them</p>



<a name="156795812"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795812" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795812">(Jan 24 2019 at 18:48)</a>:</h4>
<p>interesting yeah</p>



<a name="156795817"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795817" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795817">(Jan 24 2019 at 18:48)</a>:</h4>
<p>and yeah, that might mean that e.g. <span class="user-mention" data-user-id="116083">@pnkfelix</span> still helps with migration, but goes off to focus on other things</p>



<a name="156795840"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795840" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795840">(Jan 24 2019 at 18:49)</a>:</h4>
<p>(conversely, I'm not sure that "triage" is relevant to polonius)</p>



<a name="156795857"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795857" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Santiago Pastorino <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795857">(Jan 24 2019 at 18:49)</a>:</h4>
<p>yeah, the idea is interesting</p>



<a name="156795873"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795873" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Santiago Pastorino <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795873">(Jan 24 2019 at 18:49)</a>:</h4>
<p>and it seems also a bit refreshing</p>



<a name="156795878"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795878" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795878">(Jan 24 2019 at 18:49)</a>:</h4>
<p>needless to say if such a WG-polonius existed I would like to contribute to it as well :)</p>



<a name="156795940"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795940" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Santiago Pastorino <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795940">(Jan 24 2019 at 18:50)</a>:</h4>
<p>me too :)</p>



<a name="156795951"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795951" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795951">(Jan 24 2019 at 18:50)</a>:</h4>
<p>needless to say, i'd like everyone to contribute :)</p>



<a name="156795964"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795964" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795964">(Jan 24 2019 at 18:50)</a>:</h4>
<p>(though I don't want us to take our eye off the ball when it comes to migration)</p>



<a name="156795997"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156795997" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156795997">(Jan 24 2019 at 18:50)</a>:</h4>
<p>(ps, from my list above, I sort of forgot the epic place-2.0 work that <span class="user-mention" data-user-id="116773">@csmoe</span> and <span class="user-mention" data-user-id="116266">@Santiago Pastorino</span> have been doing, but that doesn't really feel like it belongs in NLL per se, more like general compiler refactoring)</p>



<a name="156796006"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796006" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796006">(Jan 24 2019 at 18:50)</a>:</h4>
<p>yeah, if I suddenly find time in my schedule to do a deep dive into Polonius, I'd ask to join WG-polonius</p>



<a name="156796025"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796025" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796025">(Jan 24 2019 at 18:51)</a>:</h4>
<p>but right now its not in the cards</p>



<a name="156796066"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796066" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796066">(Jan 24 2019 at 18:51)</a>:</h4>
<p>Hmm, I am liking this idea. One thing I am interested in doing a bit with Polonius is trying to dig a bit more into the design.</p>



<a name="156796078"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796078" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796078">(Jan 24 2019 at 18:51)</a>:</h4>
<p>maybe with video chats?</p>



<a name="156796149"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796149" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796149">(Jan 24 2019 at 18:52)</a>:</h4>
<p>I guess we should find out whether the polonius plan holds up when integrated a bit more into rustc, and <em>then</em> make a WG ? just in order not to become the shortest lived WG in history ? :)</p>



<a name="156796151"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796151" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796151">(Jan 24 2019 at 18:52)</a>:</h4>
<p>(by this I mean more like "why are the rules the way they are")</p>



<a name="156796155"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796155" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> blitzerr <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796155">(Jan 24 2019 at 18:52)</a>:</h4>
<blockquote>
<p>Hmm, I am liking this idea. One thing I am interested in doing a bit with Polonius is trying to dig a bit more into the design.</p>
</blockquote>
<p>It would be helpful. I know nothing about it</p>



<a name="156796177"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796177" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796177">(Jan 24 2019 at 18:52)</a>:</h4>
<blockquote>
<p>just in order not to become the shortest lived WG in history ? :)</p>
</blockquote>
<p>I think it's ok if the WG outcome is "tried it, it failed"</p>



<a name="156796182"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796182" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796182">(Jan 24 2019 at 18:52)</a>:</h4>
<p>but I also really don't expect that</p>



<a name="156796199"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796199" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796199">(Jan 24 2019 at 18:52)</a>:</h4>
<p>I guess I think it's more likely that we "evolve" the plan</p>



<a name="156796263"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796263" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> blitzerr <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796263">(Jan 24 2019 at 18:53)</a>:</h4>
<p>What are the cases it can fail ? Perf ?</p>



<a name="156796275"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796275" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796275">(Jan 24 2019 at 18:54)</a>:</h4>
<p>it's the one that comes to my mind right now</p>



<a name="156796321"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796321" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796321">(Jan 24 2019 at 18:54)</a>:</h4>
<p>I suppose, or maybe we realize the analysis is flawed in some way</p>



<a name="156796322"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796322" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796322">(Jan 24 2019 at 18:54)</a>:</h4>
<p>As someone who has been only tangentially following both projects, I would like to better understand whether we need separate Chalk vs Datafrog</p>



<a name="156796339"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796339" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> blitzerr <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796339">(Jan 24 2019 at 18:54)</a>:</h4>
<p>But isn't <span class="user-mention" data-user-id="116009">@nikomatsakis</span>  proposing a datafrog dependent querying ? So will it affect all the future plans as well ?</p>



<a name="156796342"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796342" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796342">(Jan 24 2019 at 18:54)</a>:</h4>
<p>I mean, I do get that they are different kinds of logic programming</p>



<a name="156796354"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796354" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796354">(Jan 24 2019 at 18:54)</a>:</h4>
<p>I don't know, the more I think about it, the more I feel like we should make a wg-polonius. Maybe try to "kick it off" post all hands -- not 100% sure what "kick it off" means anyway. I want to think a bit about how to manage our time, I don't want to go encouraging people to contribute and then we don't have enough time to keep things moving</p>



<a name="156796389"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796389" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796389">(Jan 24 2019 at 18:55)</a>:</h4>
<p>maybe it'll depend on the curious case of the hereditary harrop predicate :)</p>



<a name="156796399"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796399" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796399">(Jan 24 2019 at 18:55)</a>:</h4>
<p><span class="user-mention" data-user-id="116083">@pnkfelix</span> a good question, and one I would like to dig into, but perhaps not this second :)</p>



<a name="156796415"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796415" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796415">(Jan 24 2019 at 18:55)</a>:</h4>
<p>one thing I could see trying to do</p>



<a name="156796417"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796417" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796417">(Jan 24 2019 at 18:55)</a>:</h4>
<blockquote>
<p><span class="user-mention silent" data-user-id="116083">@pnkfelix</span> a good question, and one I would like to dig into, but perhaps not this second :)</p>
</blockquote>
<p>oh yeah, that was totally a penny on the rails</p>



<a name="156796419"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796419" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796419">(Jan 24 2019 at 18:55)</a>:</h4>
<p>maybe even next week</p>



<a name="156796431"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796431" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796431">(Jan 24 2019 at 18:55)</a>:</h4>
<p>is to do a "compiler lecture series" sort of thing on polonius</p>



<a name="156796439"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796439" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796439">(Jan 24 2019 at 18:56)</a>:</h4>
<p>in particular I've been wanting to kind of walk through some of the really interesting cases</p>



<a name="156796489"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796489" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796489">(Jan 24 2019 at 18:56)</a>:</h4>
<p>and try to explain (read: remember) why I setup the rules just the way I did</p>



<a name="156796497"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796497" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796497">(Jan 24 2019 at 18:56)</a>:</h4>
<p>it was definitely not accidental, and I sort of remember the process that led to them :)</p>



<a name="156796509"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796509" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796509">(Jan 24 2019 at 18:56)</a>:</h4>
<p>but there are some subtle points that are easy to overlook...</p>



<a name="156796533"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796533" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796533">(Jan 24 2019 at 18:56)</a>:</h4>
<p>this might be a chance <span class="user-mention" data-user-id="116083">@pnkfelix</span> to also cover that question</p>



<a name="156796550"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796550" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796550">(Jan 24 2019 at 18:57)</a>:</h4>
<p>(<br>
the idea would be to shcedule a recorded video chat, basically)</p>



<a name="156796560"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796560" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796560">(Jan 24 2019 at 18:57)</a>:</h4>
<p>would having this other WG not bite into your already limited time niko ?</p>



<a name="156796567"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796567" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796567">(Jan 24 2019 at 18:57)</a>:</h4>
<p>well that is the concern, I think we need to figure out the leadership story</p>



<a name="156796570"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796570" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796570">(Jan 24 2019 at 18:57)</a>:</h4>
<p>(similarly for WG-nll actually)</p>



<a name="156796575"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796575" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796575">(Jan 24 2019 at 18:57)</a>:</h4>
<p>but I feel like I am not ready to let polonius go</p>



<a name="156796577"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796577" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796577">(Jan 24 2019 at 18:57)</a>:</h4>
<p>:P</p>



<a name="156796587"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796587" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Santiago Pastorino <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796587">(Jan 24 2019 at 18:57)</a>:</h4>
<p>hahaha</p>



<a name="156796588"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796588" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Santiago Pastorino <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796588">(Jan 24 2019 at 18:57)</a>:</h4>
<p>:P</p>



<a name="156796589"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796589" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796589">(Jan 24 2019 at 18:57)</a>:</h4>
<p>(I also think that there is overlap -- esp around regions -- with the chalk work)</p>



<a name="156796604"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796604" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796604">(Jan 24 2019 at 18:58)</a>:</h4>
<p>oh yeah true</p>



<a name="156796708"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796708" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> blitzerr <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796708">(Jan 24 2019 at 18:59)</a>:</h4>
<blockquote>
<p>and try to explain (read: remember) why I setup the rules just the way I did</p>
</blockquote>
<p>Do we have to formally verify the rules ?</p>



<a name="156796712"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796712" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796712">(Jan 24 2019 at 18:59)</a>:</h4>
<p>we're kind of running up on an hour :)</p>



<a name="156796723"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796723" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796723">(Jan 24 2019 at 18:59)</a>:</h4>
<p>were <span class="user-mention" data-user-id="116118">@Matthew Jasper</span> <span class="user-mention" data-user-id="116107">@davidtwco</span> <span class="user-mention" data-user-id="116013">@qmx</span> also interested in polonius ?</p>



<a name="156796835"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796835" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796835">(Jan 24 2019 at 19:00)</a>:</h4>
<p><span class="user-mention" data-user-id="128294">@blitzerr</span> we don't normally do that, but it's an interesting question to think about I think. e.g. one thing I would like to do is to try and compare the rules more to the work that <span class="user-mention" data-user-id="120791">@RalfJ</span> and others are doing and map betwen them.</p>



<a name="156796836"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796836" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Matthew Jasper <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796836">(Jan 24 2019 at 19:00)</a>:</h4>
<p>Yes, once I have time for it...</p>



<a name="156796875"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796875" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796875">(Jan 24 2019 at 19:00)</a>:</h4>
<p>so let's do this: we'll try to schedule a polonius design chat, and maybe post all hands try to figure out WG next steps?</p>



<a name="156796888"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796888" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796888">(Jan 24 2019 at 19:01)</a>:</h4>
<p>(all hands being Feb 4-8 or something like that)</p>



<a name="156796894"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796894" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796894">(Jan 24 2019 at 19:01)</a>:</h4>
<p>i.e. week after next</p>



<a name="156796904"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156796904" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> davidtwco <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156796904">(Jan 24 2019 at 19:01)</a>:</h4>
<blockquote>
<p>were <span class="user-mention silent" data-user-id="116118">@Matthew Jasper</span> <span class="user-mention silent" data-user-id="116107">@davidtwco</span> <span class="user-mention silent" data-user-id="116013">@qmx</span> also interested in polonius ?</p>
</blockquote>
<p>I've not really looked at it at all. I've not really been focusing on any area in particular as the WG-NLL work wound down. I think I'm going to hold off jumping in until after the All Hands to see what happens with working groups and if there are any interesting new ones.</p>



<a name="156797051"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156797051" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> qmx <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156797051">(Jan 24 2019 at 19:03)</a>:</h4>
<p>I only stopped playing with polonius/NLL because wg-grammar takes all my time nowadays</p>



<a name="156797062"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156797062" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> qmx <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156797062">(Jan 24 2019 at 19:03)</a>:</h4>
<p>but I still keep paying attention here in the hopes I'll have some spare cycles :)</p>



<a name="156797130"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156797130" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156797130">(Jan 24 2019 at 19:04)</a>:</h4>
<p>did we want to touch on other subjects today ?</p>



<a name="156797146"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156797146" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156797146">(Jan 24 2019 at 19:04)</a>:</h4>
<p>I feel like we're out of time, but I'd definitely like to know if there are things we missed that we should schedule for another time</p>



<a name="156797148"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156797148" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156797148">(Jan 24 2019 at 19:04)</a>:</h4>
<p>BTW: on the topic of move and initialization analysis, one thing I might mention is that the Lark compiler <a href="https://github.com/lark-exploration/lark/blob/46863c4120a3bfd5a7d95b148111e83e752d7955/components/lark-type-check/src/full_inference/analysis/initialization.rs" target="_blank" title="https://github.com/lark-exploration/lark/blob/46863c4120a3bfd5a7d95b148111e83e752d7955/components/lark-type-check/src/full_inference/analysis/initialization.rs">does this with datafrog already</a>, though I've not yet hooked it up to polonius (so its borrow checker isn't great). So e.g. <span class="user-mention" data-user-id="116083">@pnkfelix</span> if you wanted to think about what it might mean ...</p>



<a name="156797173"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156797173" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156797173">(Jan 24 2019 at 19:04)</a>:</h4>
<p>(...another thing it'd be fun to find a bit of time to talk about)</p>



<a name="156797208"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156797208" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156797208">(Jan 24 2019 at 19:05)</a>:</h4>
<p>interesting</p>



<a name="156797221"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156797221" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156797221">(Jan 24 2019 at 19:05)</a>:</h4>
<p>I kind of implemented it in a few hours so I don't really remember if it's equivalent to what rust does today, but I think it roughly is</p>



<a name="156797224"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156797224" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156797224">(Jan 24 2019 at 19:05)</a>:</h4>
<p>but perhaps that's part of the point: I implemented it in a few hours ;)</p>



<a name="156797238"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156797238" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156797238">(Jan 24 2019 at 19:06)</a>:</h4>
<p>:)</p>



<a name="156797382"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156797382" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156797382">(Jan 24 2019 at 19:07)</a>:</h4>
<p>so migration, 2PB, Polonius, Polonius WG, are we missing something ?</p>



<a name="156797478"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156797478" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156797478">(Jan 24 2019 at 19:09)</a>:</h4>
<p>kinda the closure work, lexical solver conversion, code cleanup  (including neoplace maybe)</p>



<a name="156797604"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156797604" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> blitzerr <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156797604">(Jan 24 2019 at 19:11)</a>:</h4>
<p>(Maybe the talk on Polonius and Lark ?)</p>



<a name="156797646"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/steering%20meeting%202019.01.24/near/156797646" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lqd <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/steering.20meeting.202019.2E01.2E24.html#156797646">(Jan 24 2019 at 19:11)</a>:</h4>
<p>(I have to take off, thanks all for the meeting. Good afternoon/evening everyone <span aria-label="wave" class="emoji emoji-1f44b" role="img" title="wave">:wave:</span> )</p>



<hr><p>Last updated: Aug 07 2021 at 22:04 UTC</p>
</html>